BoilerFaultCodesYour boiler's main control unit has detected an internal communication error and is struggling to manage the various components of the heating system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Control unit is fault manager
What causes this fault?
This fault occurs when the boiler's internal computer chips stop being able to talk to each other reliably across the main circuit board. It is usually caused by a physical degradation of the electronic soldering or a failure in the communication module that acts as the 'translator' for the system's instructions. When these signals are interrupted, the boiler shuts down because it can no longer safely coordinate the fan, pump, and burner.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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